The aim of this ex vivo study was to compare the performance of the visual ICDAS II scale and two fluorescence methods (DIAGNOdent Pen and VistaCam iX) in detecting occlusal caries lesions in permanent teeth using cone beam computed tomography (CBCT) as a reference test.One hundred-sixty molars and premolars were qualified for the study. The visual, the DIAGNOdent Pen and VistaCam iX examinations were carried out by two examiners. The actual extent of the lesions was determined using CBCT. For the three methods, inter- and intra-examiner reproducibility was calculated using intraclass correlation coefficient. The sensitivity, specificity, and accuracy of these methods were compared using the mid-P McNemar test. The level of significance was set at p < 0.05.For all data, intraclass-correlation coefficients (ICC) for intra- and inter-examiner reproducibility were high. With regard to the enamel threshold, the sensitivity and accuracy were significantly higher for VistaCam iX and ICDAS II compared with the DIAGNOdent Pen (p < 0.05). The results obtained with the DIAGNOdentu Pen indicated significantly higher specificity values for the enamel threshold (p < 0.05). The results obtained with the VistaCam iX showed the lowest sensitivity but the significantly highest specificity and accuracy for the dentin threshold (p < 0.05).The ICDAS II is an effective method for detecting early carious lesions, characterized by a higher sensitivity compared with devices using fluorescence. To improve the diagnostic efficiency of the evaluated devices, modifying the cut-off values recommended by the manufacturers should be considered.